Lucas v. South Carolina Coastal Council
In Lucas v. South Carolina Coastal Council, 505 U.S. 1003, 1017 (1992), the U.S. Supreme Court held that when a regulation has the effect of a permanent deprivation of all beneficial use, then it triggers the Takings Clause requiring compensation to the owner.
This was justified by what the Court later called exceptional circumstances in the "relatively rare situations where the government has deprived a landowner of all economically beneficial uses," and thus there is no "average reciprocity of advantage" or extreme burden on government such that it could not go on if required to pay for every such restriction. 505 U.S. at 1017-1018.
Justice Antonin Scalia wrote the decision for a 6-2 Court, with Justice Byron White joining him and Justice Anthony Kennedy concurring. Justice David Souter write a "statement" that he preferred to dismiss the case on the basis of an improvident grant of certiorari.